Ten Precautions for LED Street LightsLED Street Lights

Ten Precautions for LED Street Lights-LED Street Lights A large number of applications of LED street lamps in today's society have played a decisive role in the progress of lighting engineering, especially the two aspects of energy saving and low carbon of LED street lamps have made important contributions to society. Let's talk about the process of daily use. 10 things that LED street lights should pay attention to. 1. LED street light power supply must be constant current The lighting material characteristics of LED street lamps determine that it is affected by the environment. For example, as the temperature changes, the current of the LED will increase; in addition, the current of the LED will also increase with the increase of the voltage. If the long-term work exceeds the rated current, it will greatly shorten the service life of the LED lamp beads.

LED constant current is to ensure that the current value of its work remains unchanged when environmental factors such as temperature and voltage change. 2. Constant current accuracy of LED street light power supply The constant current accuracy of some power supplies on the market is poor, the error may reach ±8%, and the constant current error is too large. The general requirement is within ±3%.

According to the design scheme of 3%. The production power supply needs to be fine-tuned to achieve ±3% error. 3. Working voltage of LED street light power supply Generally, the recommended operating voltage of LEDs is 3.0-3.5V. After testing, most of them work at 3.2V, so the calculation formula based on 3.2V is more reasonable.

The total voltage of N lamp beads in series = 3.2*N 4. What is the most suitable working current of the LED street light power supply? For example, the rated working current of LED is 350mA, some factories use it up at the beginning, and design 350mA, in fact, the work heat is very serious under this current, after many comparison tests, it is ideal to design it as 320mA . Minimize heat generation, so that more electrical energy can be converted into visible light energy. 5. How wide is the series-parallel connection and wide voltage of the LED street lamp power board? In order to make the LED street light power supply work in a relatively wide input voltage range of AC85-265V, the LED series-parallel connection of the light board is very important.

Try not to use wide voltage, can be divided into AC220V, AC110V as much as possible, so as to ensure the reliability of power supply. Since the current power supply is generally a non-isolated step-down constant current power supply, when the required voltage is 110V, the output voltage should not exceed 70V, and the number of series connections should not exceed 23. When the input voltage is 220V, the output voltage can reach 156V.

That is to say, the number of series connection does not exceed 45 strings. The number of parallel connections should not be too large, otherwise the working current will be too large and the power supply will heat up severely. There is also a wide voltage solution, APFC active power compensation is to first use L6561/7527 to raise the voltage to 400V, and then step down, which is equivalent to two switching power supplies.

This program is only used under certain conditions. 6. Isolation/non-isolation Generally, if the isolated power supply is made into 15W and placed in the power tube of the LED street lamp, the transformer is very bulky and it is difficult to put it in. It mainly depends on the space structure and depends on the specific situation. Generally, the isolation can only reach 15W, and the ones exceeding 15W are rare, and the price is very expensive.

Therefore, the price-performance ratio of isolation is not high. Generally, non-isolation is the mainstream, and the volume can be made smaller, and the minimum height can be 8mm. In fact, there is no problem if non-isolation safety measures are taken well. If space permits, it can also be used as an isolated power supply. 7. How can the LED street lamp power supply match the lamp bead board? In fact, if you choose the best series-parallel connection, the voltage and current applied to each LED will be the same, but the power supply will have the best performance.

The best way is to communicate with the power supply manufacturer first and make a tailor-made one. Or produce your own power supply. 8. LED street light power efficiency The input power minus the output power value, this parameter is particularly important, the greater the value, the lower the efficiency, which means that a large part of the input power is converted into heat and emitted; if it is installed in the lamp, it will generate a very high temperature , plus the heat emitted by a luminous efficiency ratio of our LED, it will superimpose a higher temperature. And the life of all electronic parts inside our power supply will be shortened as the temperature rises. So efficiency is the most important factor that determines the life of the power supply. The fundamental factor is that the efficiency cannot be too low, otherwise the heat consumed on the power supply will be too large.

The efficiency of the non-isolated type is higher than that of the isolated type, generally above 80%. However, the efficiency is related to the matching connection method of the light board. 9. Heat dissipation of LED street light source The main factor of the heat dissipation solution is that the lifespan of LED street lamp beads can be greatly extended when used under the condition of not overheating. Generally, aluminum alloy is used, which is easier to dissipate heat. That is to say, the LED street light power beads are pasted on the aluminum substrate, and the external heat dissipation area is enlarged as much as possible. 10. LED street lamp power cooling The main factor for heat dissipation is that the LED street lamp power supply beads can greatly prolong their life when used under the condition of not overheating. Generally, aluminum alloy radiators are used, which are easier to dissipate heat.

That is to say, the LED street light power beads are pasted on the aluminum substrate, and the external heat dissipation area is enlarged as much as possible. The above ten items have analyzed the key points of LED street lamps in detail for us. Reasonable use will improve the service life of LED street lamps and reduce production costs. I believe that anyone will be very interested.